Early detection of bladder cancer remains an important problem in management of bladder cancer. Urinary cytology with specificity and sensitivity of 50-80% (Murphy et al., 1984) is hampered by subjective observer error, the importance of processing techniques, and artefacts introduced by inflammation or chemotherapy (Chopin et al., 1985). More recently developed methods have not resolved the aforementioned problems. For example, flow cytometry (for review, see Russell et al., 1988a) requires substantial equipment and a large number of shed cells. Furthermore, the correlation between ploidy and prognosis is imperfect. Similarly, immunohistological staining for ABO blood group antigens or the T-(Thomsen Freidenreich) antigen (Limas and Lange, 1980) or carcinoembryonic antigen (Huland et al., 1983) gives variable correlation with prognosis and has major limitations for early diagnosis of new or recurrent disease.
Recently, more useful tumour markers have been identified by using monoclonal antibodies raised against bladder carcinomas. These have been used to detect bladder cancer cells in bladder washings (Chopin et al., 1985).